It is already known from U.S. Pat. No. 2,327,237 that the guide surfaces on the webs of a cage can be made concave to fit the lateral surface of the roller. The radially inward and outward edge areas of the webs thus wrap around part of the roller and form a positive interlock which holds the roller in position. The degree of positive engagement depends on the radial position of the roller in the cage, that is, on the position of the pitch circle of the rollers with respect to the outside lateral surface of the cage and its bore. In addition, there must be at least one circumferential area where the edges of the webs wrap only slightly around the roller, so that it is possible to insert the rollers into the cage or so that, by taking advantage of the elasticity of the cage, the rollers can be snapped into place. For the sake of good lubrication, the guide surfaces themselves are optimized with respect to their curvature and the gap between them and the lateral surface of the roller. To make sure that the lubricant is properly distributed, the edge areas should not scrape the lubricant off the roller when the cage sags. This is not guaranteed in the known cage.